1. Field of the Invention
The present invention relates to a card-type portable data storage device and a portable data storage device connection mechanism comprising this data portable storage device and a connector terminal to which this storage device is connected, and, in particular, to a dustproof and dripproof construction of said storage device.
2. Description of the Related Art
FIG. 6 is a cross-sectional view showing a conventional portable data storage device inserted into a terminal connector. FIG. 6 shows which a card-type portable data storage device 1 inserted into an insertion hole 5a of a terminal connector 5 disposed on the board 7 of a terminal. A plurality of female electrodes 2a are arrayed in the connector section 2 of the portable data storage device 1. The same number of male electrodes 6 are disposed inside the insertion hole 5a of the terminal connector 5, the male electrodes 6 being inserted into the female electrodes 2a of the portable data storage device 1 thereby making an electrical connection. In such a state in which the portable data storage device 1 is inserted into the terminal connector 5, there is inevitably a clearance between the above two, and dirt, dust, and the like are bound to enter through the clearance. The arrow symbol A in FIG. 6 indicates the route of the entry of dust, water, oil, corrosive gases, etc. from outside. There is a possibility that, in particular, water, oil, and corrosive gases will enter through the press-fit section for the male electrodes 6 on the terminal connector 5.
A current which flows through the electrode sections of the male electrodes 6 and of the female electrodes 2a is generally small, on the order of .mu.A to mA in the case of a signal line. Therefore, if dust sticks, there is a danger that a defective contact will occur, causing data stored in the portable data storage device 1 to be destroyed. There is also a danger that adhesion of a corrosive gas or a liquid may corrode the electrode sections. Where the portable data storage device 1 has a battery for data backup, there is a possibility that dirt, dust, etc. will enter from the section between a battery holder for housing this battery (not shown) and the portable data storage device main body.
In the conventional contact-point portable data storage device 1 and the terminal connector 5 shown in FIG. 6, it is quite difficult to prevent the entry of dirt, dust, etc. into the terminal connector 5 when the portable data storage device 1 is inserted into the terminal connector 5. For this reason, there has been available a noncontact type portable data storage device which is not susceptible to influences from the environment of a place where it is used, for example, a device in which magnetic coupling is used. However, most of these devices read and write data by serial transmission. This serial transmission has a drawback in that its data transmission speed is slow. There is also a drawback in that the memory storage capacity of such a device is small. That is, in the present situation, no portable data storage device is available which is not easily susceptible to adverse environmental influences which transmits data at a high speed, and which has a large storage capacity.
In the conventional contact-point portable data storage device connection mechanism, it is impossible to prevent the entry of dirt, dust, corrosive gas, or liquid at a clearance space between a portable storage device and a terminal connector. Therefore, it cannot be used in stringent environmental conditions, and there arises a problem in that the field of applications of the portable data storage device is limited.